Texture wont change after duplication
A few things to try:

1) Select the new object, and remove the old material, then add a new material. This should disconnect the material of the new object from the old one.

2) Select the old object and go to Object > Apply > Make duplicates real. This will make the duplicates connected to the object (in case somehow the object is a duplicate) a real object.

3) Select the new object, and go to Object > Users > Make single user-Object &amp; Data &amp; Materials &amp; tex. 

If one of these three things do not fix the problem, I don't know what can.